<?php

//
// $Id: sphinxapi.php 2055 2009-11-06 23:09:58Z shodan $
//

//
// Copyright (c) 2001-2008, Andrew Aksyonoff. All rights reserved.
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License. You should have
// received a copy of the GPL license along with this program; if you
// did not, you can find it at http://www.gnu.org/
//

/////////////////////////////////////////////////////////////////////////////
// PHP version of Sphinx searchd client (PHP API)
/////////////////////////////////////////////////////////////////////////////

/// known searchd commands
define ( "SEARCHD_COMMAND_SEARCH",	0 );
define ( "SEARCHD_COMMAND_EXCERPT",	1 );
define ( "SEARCHD_COMMAND_UPDATE",	2 );
define ( "SEARCHD_COMMAND_KEYWORDS",3 );
define ( "SEARCHD_COMMAND_PERSIST",	4 );
define ( "SEARCHD_COMMAND_STATUS",	5 );
define ( "SEARCHD_COMMAND_QUERY",	6 );

/// current client-side command implementation versions
define ( "VER_COMMAND_SEARCH",		0x116 );
define ( "VER_COMMAND_EXCERPT",		0x100 );
define ( "VER_COMMAND_UPDATE",		0x102 );
define ( "VER_COMMAND_KEYWORDS",	0x100 );
define ( "VER_COMMAND_STATUS",		0x100 );
define ( "VER_COMMAND_QUERY",		0x100 );

/// known searchd status codes
define ( "SEARCHD_OK",				0 );
define ( "SEARCHD_ERROR",			1 );
define ( "SEARCHD_RETRY",			2 );
define ( "SEARCHD_WARNING",			3 );

/// known match modes
define ( "SPH_MATCH_ALL",			0 );
define ( "SPH_MATCH_ANY",			1 );
define ( "SPH_MATCH_PHRASE",		2 );
define ( "SPH_MATCH_BOOLEAN",		3 );
define ( "SPH_MATCH_EXTENDED",		4 );
define ( "SPH_MATCH_FULLSCAN",		5 );
define ( "SPH_MATCH_EXTENDED2",		6 );	// extended engine V2 (TEMPORARY, WILL BE REMOVED)

/// known ranking modes (ext2 only)
define ( "SPH_RANK_PROXIMITY_BM25",	0 );	///< default mode, phrase proximity major factor and BM25 minor one
define ( "SPH_RANK_BM25",			1 );	///< statistical mode, BM25 ranking only (faster but worse quality)
define ( "SPH_RANK_NONE",			2 );	///< no ranking, all matches get a weight of 1
define ( "SPH_RANK_WORDCOUNT",		3 );	///< simple word-count weighting, rank is a weighted sum of per-field keyword occurence counts
define ( "SPH_RANK_PROXIMITY",		4 );
define ( "SPH_RANK_MATCHANY",		5 );
define ( "SPH_RANK_FIELDMASK",		6 );

/// known sort modes
define ( "SPH_SORT_RELEVANCE",		0 );
define ( "SPH_SORT_ATTR_DESC",		1 );
define ( "SPH_SORT_ATTR_ASC",		2 );
define ( "SPH_SORT_TIME_SEGMENTS", 	3 );
define ( "SPH_SORT_EXTENDED", 		4 );
define ( "SPH_SORT_EXPR", 			5 );

/// known filter types
define ( "SPH_FILTER_VALUES",		0 );
define ( "SPH_FILTER_RANGE",		1 );
define ( "SPH_FILTER_FLOATRANGE",	2 );

/// known attribute types
define ( "SPH_ATTR_INTEGER",		1 );
define ( "SPH_ATTR_TIMESTAMP",		2 );
define ( "SPH_ATTR_ORDINAL",		3 );
define ( "SPH_ATTR_BOOL",			4 );
define ( "SPH_ATTR_FLOAT",			5 );
define ( "SPH_ATTR_BIGINT",			6 );
define ( "SPH_ATTR_MULTI",			0x40000000 );

/// known grouping functions
define ( "SPH_GROUPBY_DAY",			0 );
define ( "SPH_GROUPBY_WEEK",		1 );
define ( "SPH_GROUPBY_MONTH",		2 );
define ( "SPH_GROUPBY_YEAR",		3 );
define ( "SPH_GROUPBY_ATTR",		4 );
define ( "SPH_GROUPBY_ATTRPAIR",	5 );

// important properties of PHP's integers:
//  - always signed (one bit short of PHP_INT_SIZE)
//  - conversion from string to int is saturated
//  - float is double
//  - div converts arguments to floats
//  - mod converts arguments to ints

// the packing code below works as follows:
//  - when we got an int, just pack it
//    if performance is a problem, this is the branch users should aim for
//
//  - otherwise, we got a number in string form
//    this might be due to different reasons, but we assume that this is
//    because it didn't fit into PHP int
//
//  - factor the string into high and low ints for packing
//    - if we have bcmath, then it is used
//    - if we don't, we have to do it manually (this is the fun part)
//
//    - x64 branch does factoring using ints
//    - x32 (ab)uses floats, since we can't fit unsigned 32-bit number into an int
//
// unpacking routines are pretty much the same.
//  - return ints if we can
//  - otherwise format number into a string

/// pack 64-bit signed
function sphPackI64 ( $v )
{
    assert ( is_numeric($v) );

    // x64
    if ( PHP_INT_SIZE>=8 )
    {
        $v = (int)$v;
        return pack ( "NN", $v>>32, $v&0xFFFFFFFF );
    }

    // x32, int
    if ( is_int($v) )
        return pack ( "NN", $v < 0 ? -1 : 0, $v );

    // x32, bcmath
    if ( function_exists("bcmul") )
    {
        if ( bccomp ( $v, 0 ) == -1 )
            $v = bcadd ( "18446744073709551616", $v );
        $h = bcdiv ( $v, "4294967296", 0 );
        $l = bcmod ( $v, "4294967296" );
        return pack ( "NN", (float)$h, (float)$l ); // conversion to float is intentional; int would lose 31st bit
    }

    // x32, no-bcmath
    $p = max(0, strlen($v) - 13);
    $lo = abs((float)substr($v, $p));
    $hi = abs((float)substr($v, 0, $p));

    $m = $lo + $hi*1316134912.0; // (10 ^ 13) % (1 << 32) = 1316134912
    $q = floor($m/4294967296.0);
    $l = $m - ($q*4294967296.0);
    $h = $hi*2328.0 + $q; // (10 ^ 13) / (1 << 32) = 2328

    if ( $v<0 )
    {
        if ( $l==0 )
            $h = 4294967296.0 - $h;
        else
        {
            $h = 4294967295.0 - $h;
            $l = 4294967296.0 - $l;
        }
    }
    return pack ( "NN", $h, $l );
}

/// pack 64-bit unsigned
function sphPackU64 ( $v )
{
    assert ( is_numeric($v) );

    // x64
    if ( PHP_INT_SIZE>=8 )
    {
        assert ( $v>=0 );

        // x64, int
        if ( is_int($v) )
            return pack ( "NN", $v>>32, $v&0xFFFFFFFF );

        // x64, bcmath
        if ( function_exists("bcmul") )
        {
            $h = bcdiv ( $v, 4294967296, 0 );
            $l = bcmod ( $v, 4294967296 );
            return pack ( "NN", $h, $l );
        }

        // x64, no-bcmath
        $p = max ( 0, strlen($v) - 13 );
        $lo = (int)substr ( $v, $p );
        $hi = (int)substr ( $v, 0, $p );

        $m = $lo + $hi*1316134912;
        $l = $m % 4294967296;
        $h = $hi*2328 + (int)($m/4294967296);

        return pack ( "NN", $h, $l );
    }

    // x32, int
    if ( is_int($v) )
        return pack ( "NN", 0, $v );

    // x32, bcmath
    if ( function_exists("bcmul") )
    {
        $h = bcdiv ( $v, "4294967296", 0 );
        $l = bcmod ( $v, "4294967296" );
        return pack ( "NN", (float)$h, (float)$l ); // conversion to float is intentional; int would lose 31st bit
    }

    // x32, no-bcmath
    $p = max(0, strlen($v) - 13);
    $lo = (float)substr($v, $p);
    $hi = (float)substr($v, 0, $p);

    $m = $lo + $hi*1316134912.0;
    $q = floor($m / 4294967296.0);
    $l = $m - ($q * 4294967296.0);
    $h = $hi*2328.0 + $q;

    return pack ( "NN", $h, $l );
}

// unpack 64-bit unsigned
function sphUnpackU64 ( $v )
{
    list ( $hi, $lo ) = array_values ( unpack ( "N*N*", $v ) );

    if ( PHP_INT_SIZE>=8 )
    {
        if ( $hi<0 ) $hi += (1<<32); // because php 5.2.2 to 5.2.5 is totally fucked up again
        if ( $lo<0 ) $lo += (1<<32);

        // x64, int
        if ( $hi<=2147483647 )
            return ($hi<<32) + $lo;

        // x64, bcmath
        if ( function_exists("bcmul") )
            return bcadd ( $lo, bcmul ( $hi, "4294967296" ) );

        // x64, no-bcmath
        $C = 100000;
        $h = ((int)($hi / $C) << 32) + (int)($lo / $C);
        $l = (($hi % $C) << 32) + ($lo % $C);
        if ( $l>$C )
        {
            $h += (int)($l / $C);
            $l  = $l % $C;
        }

        if ( $h==0 )
            return $l;
        return sprintf ( "%d%05d", $h, $l );
    }

    // x32, int
    if ( $hi==0 )
    {
        if ( $lo>0 )
            return $lo;
        return sprintf ( "%u", $lo );
    }

    $hi = sprintf ( "%u", $hi );
    $lo = sprintf ( "%u", $lo );

    // x32, bcmath
    if ( function_exists("bcmul") )
        return bcadd ( $lo, bcmul ( $hi, "4294967296" ) );

    // x32, no-bcmath
    $hi = (float)$hi;
    $lo = (float)$lo;

    $q = floor($hi/10000000.0);
    $r = $hi - $q*10000000.0;
    $m = $lo + $r*4967296.0;
    $mq = floor($m/10000000.0);
    $l = $m - $mq*10000000.0;
    $h = $q*4294967296.0 + $r*429.0 + $mq;

    $h = sprintf ( "%.0f", $h );
    $l = sprintf ( "%07.0f", $l );
    if ( $h=="0" )
        return sprintf( "%.0f", (float)$l );
    return $h . $l;
}

// unpack 64-bit signed
function sphUnpackI64 ( $v )
{
    list ( $hi, $lo ) = array_values ( unpack ( "N*N*", $v ) );

    // x64
    if ( PHP_INT_SIZE>=8 )
    {
        if ( $hi<0 ) $hi += (1<<32); // because php 5.2.2 to 5.2.5 is totally fucked up again
        if ( $lo<0 ) $lo += (1<<32);

        return ($hi<<32) + $lo;
    }

    // x32, int
    if ( $hi==0 )
    {
        if ( $lo>0 )
            return $lo;
        return sprintf ( "%u", $lo );
    }
    // x32, int
    elseif ( $hi==-1 )
    {
        if ( $lo<0 )
            return $lo;
        return sprintf ( "%.0f", $lo - 4294967296.0 );
    }

    $neg = "";
    $c = 0;
    if ( $hi<0 )
    {
        $hi = ~$hi;
        $lo = ~$lo;
        $c = 1;
        $neg = "-";
    }

    $hi = sprintf ( "%u", $hi );
    $lo = sprintf ( "%u", $lo );

    // x32, bcmath
    if ( function_exists("bcmul") )
        return $neg . bcadd ( bcadd ( $lo, bcmul ( $hi, "4294967296" ) ), $c );

    // x32, no-bcmath
    $hi = (float)$hi;
    $lo = (float)$lo;

    $q = floor($hi/10000000.0);
    $r = $hi - $q*10000000.0;
    $m = $lo + $r*4967296.0;
    $mq = floor($m/10000000.0);
    $l = $m - $mq*10000000.0 + $c;
    $h = $q*4294967296.0 + $r*429.0 + $mq;
    if ( $l==10000000 )
    {
        $l = 0;
        $h += 1;
    }

    $h = sprintf ( "%.0f", $h );
    $l = sprintf ( "%07.0f", $l );
    if ( $h=="0" )
        return $neg . sprintf( "%.0f", (float)$l );
    return $neg . $h . $l;
}


function sphFixUint ( $value )
{
    if ( PHP_INT_SIZE>=8 )
    {
        // x64 route, workaround broken unpack() in 5.2.2+
        if ( $value<0 ) $value += (1<<32);
        return $value;
    }
    else
    {
        // x32 route, workaround php signed/unsigned braindamage
        return sprintf ( "%u", $value );
    }
}


/// sphinx searchd client class
class SphinxClient
{
    var $_host;			///< searchd host (default is "localhost")
    var $_port;			///< searchd port (default is 9312)
    var $_offset;		///< how many records to seek from result-set start (default is 0)
    var $_limit;		///< how many records to return from result-set starting at offset (default is 20)
    var $_mode;			///< query matching mode (default is SPH_MATCH_ALL)
    var $_weights;		///< per-field weights (default is 1 for all fields)
    var $_sort;			///< match sorting mode (default is SPH_SORT_RELEVANCE)
    var $_sortby;		///< attribute to sort by (defualt is "")
    var $_min_id;		///< min ID to match (default is 0, which means no limit)
    var $_max_id;		///< max ID to match (default is 0, which means no limit)
    var $_filters;		///< search filters
    var $_groupby;		///< group-by attribute name
    var $_groupfunc;	///< group-by function (to pre-process group-by attribute value with)
    var $_groupsort;	///< group-by sorting clause (to sort groups in result set with)
    var $_groupdistinct;///< group-by count-distinct attribute
    var $_maxmatches;	///< max matches to retrieve
    var $_cutoff;		///< cutoff to stop searching at (default is 0)
    var $_retrycount;	///< distributed retries count
    var $_retrydelay;	///< distributed retries delay
    var $_anchor;		///< geographical anchor point
    var $_indexweights;	///< per-index weights
    var $_ranker;		///< ranking mode (default is SPH_RANK_PROXIMITY_BM25)
    var $_maxquerytime;	///< max query time, milliseconds (default is 0, do not limit)
    var $_fieldweights;	///< per-field-name weights
    var $_overrides;	///< per-query attribute values overrides
    var $_select;		///< select-list (attributes or expressions, with optional aliases)

    var $_error;		///< last error message
    var $_warning;		///< last warning message
    var $_connerror;		///< connection error vs remote error flag

    var $_reqs;			///< requests array for multi-query
    var $_mbenc;		///< stored mbstring encoding
    var $_arrayresult;	///< whether $result["matches"] should be a hash or an array
    var $_timeout;		///< connect timeout

    /////////////////////////////////////////////////////////////////////////////
    // common stuff
    /////////////////////////////////////////////////////////////////////////////

    /// create a new client object and fill defaults
    function SphinxClient ()
    {
        // per-client-object settings
        $this->_host		= "localhost";
        $this->_port		= 9312;
        $this->_path		= false;
        $this->_socket		= false;

        // per-query settings
        $this->_offset		= 0;
        $this->_limit		= 20;
        $this->_mode		= SPH_MATCH_ALL;
        $this->_weights		= array ();
        $this->_sort		= SPH_SORT_RELEVANCE;
        $this->_sortby		= "";
        $this->_min_id		= 0;
        $this->_max_id		= 0;
        $this->_filters		= array ();
        $this->_groupby		= "";
        $this->_groupfunc	= SPH_GROUPBY_DAY;
        $this->_groupsort	= "@group desc";
        $this->_groupdistinct= "";
        $this->_maxmatches	= 1000;
        $this->_cutoff		= 0;
        $this->_retrycount	= 0;
        $this->_retrydelay	= 0;
        $this->_anchor		= array ();
        $this->_indexweights= array ();
        $this->_ranker		= SPH_RANK_PROXIMITY_BM25;
        $this->_maxquerytime= 0;
        $this->_fieldweights= array();
        $this->_overrides 	= array();
        $this->_select		= "*";

        $this->_error		= ""; // per-reply fields (for single-query case)
        $this->_warning		= "";
        $this->_connerror	= false;

        $this->_reqs		= array ();	// requests storage (for multi-query case)
        $this->_mbenc		= "";
        $this->_arrayresult	= false;
        $this->_timeout		= 0;
    }

    function __destruct()
    {
        if ( $this->_socket !== false )
            fclose ( $this->_socket );
    }

    /// get last error message (string)
    function GetLastError ()
    {
        return $this->_error;
    }

    /// get last warning message (string)
    function GetLastWarning ()
    {
        return $this->_warning;
    }

    /// get last error flag (to tell network connection errors from searchd errors or broken responses)
    function IsConnectError()
    {
        return $this->_connerror;
    }

    /// set searchd host name (string) and port (integer)
    function SetServer ( $host, $port = 0 )
    {
        assert ( is_string($host) );
        if ( $host[0] == '/')
        {
            $this->_path = 'unix://' . $host;
            return;
        }
        if ( substr ( $host, 0, 7 )=="unix://" )
        {
            $this->_path = $host;
            return;
        }

        assert ( is_int($port) );
        $this->_host = $host;
        $this->_port = $port;
        $this->_path = '';

    }

    /// set server connection timeout (0 to remove)
    function SetConnectTimeout ( $timeout )
    {
        assert ( is_numeric($timeout) );
        $this->_timeout = $timeout;
    }


    function _Send ( $handle, $data, $length )
    {
        if ( feof($handle) || fwrite ( $handle, $data, $length ) !== $length )
        {
            $this->_error = 'connection unexpectedly closed (timed out?)';
            $this->_connerror = true;
            return false;
        }
        return true;
    }

    /////////////////////////////////////////////////////////////////////////////

    /// enter mbstring workaround mode
    function _MBPush ()
    {
        $this->_mbenc = "";
        if ( ini_get ( "mbstring.func_overload" ) & 2 )
        {
            $this->_mbenc = mb_internal_encoding();
            mb_internal_encoding ( "latin1" );
        }
    }

    /// leave mbstring workaround mode
    function _MBPop ()
    {
        if ( $this->_mbenc )
            mb_internal_encoding ( $this->_mbenc );
    }

    /// connect to searchd server
    function _Connect ()
    {
        if ( $this->_socket!==false )
        {
            // we are in persistent connection mode, so we have a socket
            // however, need to check whether it's still alive
            if ( !@feof ( $this->_socket ) )
                return $this->_socket;

            // force reopen
            $this->_socket = false;
        }

        $errno = 0;
        $errstr = "";
        $this->_connerror = false;

        if ( $this->_path )
        {
            $host = $this->_path;
            $port = 0;
        }
        else
        {
            $host = $this->_host;
            $port = $this->_port;
        }

        if ( $this->_timeout<=0 )
            $fp = @fsockopen ( $host, $port, $errno, $errstr );
        else
            $fp = @fsockopen ( $host, $port, $errno, $errstr, $this->_timeout );

        if ( !$fp )
        {
            if ( $this->_path )
                $location = $this->_path;
            else
                $location = "{$this->_host}:{$this->_port}";

            $errstr = trim ( $errstr );
            $this->_error = "connection to $location failed (errno=$errno, msg=$errstr)";
            $this->_connerror = true;
            return false;
        }

        // send my version
        // this is a subtle part. we must do it before (!) reading back from searchd.
        // because otherwise under some conditions (reported on FreeBSD for instance)
        // TCP stack could throttle write-write-read pattern because of Nagle.
        if ( !$this->_Send ( $fp, pack ( "N", 1 ), 4 ) )
        {
            fclose ( $fp );
            $this->_error = "failed to send client protocol version";
            return false;
        }

        // check version
        list(,$v) = unpack ( "N*", fread ( $fp, 4 ) );
        $v = (int)$v;
        if ( $v<1 )
        {
            fclose ( $fp );
            $this->_error = "expected searchd protocol version 1+, got version '$v'";
            return false;
        }

        return $fp;
    }

    /// get and check response packet from searchd server
    function _GetResponse ( $fp, $client_ver )
    {
        $response = "";
        $len = 0;

        $header = fread ( $fp, 8 );
        if ( strlen($header)==8 )
        {
            list ( $status, $ver, $len ) = array_values ( unpack ( "n2a/Nb", $header ) );
            $left = $len;
            while ( $left>0 && !feof($fp) )
            {
                $chunk = fread ( $fp, $left );
                if ( $chunk )
                {
                    $response .= $chunk;
                    $left -= strlen($chunk);
                }
            }
        }
        if ( $this->_socket === false )
            fclose ( $fp );

        // check response
        $read = strlen ( $response );
        if ( !$response || $read!=$len )
        {
            $this->_error = $len
                ? "failed to read searchd response (status=$status, ver=$ver, len=$len, read=$read)"
                : "received zero-sized searchd response";
            return false;
        }

        // check status
        if ( $status==SEARCHD_WARNING )
        {
            list(,$wlen) = unpack ( "N*", substr ( $response, 0, 4 ) );
            $this->_warning = substr ( $response, 4, $wlen );
            return substr ( $response, 4+$wlen );
        }
        if ( $status==SEARCHD_ERROR )
        {
            $this->_error = "searchd error: " . substr ( $response, 4 );
            return false;
        }
        if ( $status==SEARCHD_RETRY )
        {
            $this->_error = "temporary searchd error: " . substr ( $response, 4 );
            return false;
        }
        if ( $status!=SEARCHD_OK )
        {
            $this->_error = "unknown status code '$status'";
            return false;
        }

        // check version
        if ( $ver<$client_ver )
        {
            $this->_warning = sprintf ( "searchd command v.%d.%d older than client's v.%d.%d, some options might not work",
                $ver>>8, $ver&0xff, $client_ver>>8, $client_ver&0xff );
        }

        return $response;
    }

    /////////////////////////////////////////////////////////////////////////////
    // searching
    /////////////////////////////////////////////////////////////////////////////

    /// set offset and count into result set,
    /// and optionally set max-matches and cutoff limits
    function SetLimits ( $offset, $limit, $max=0, $cutoff=0 )
    {
        assert ( is_int($offset) );
        assert ( is_int($limit) );
        assert ( $offset>=0 );
        assert ( $limit>0 );
        assert ( $max>=0 );
        $this->_offset = $offset;
        $this->_limit = $limit;
        if ( $max>0 )
            $this->_maxmatches = $max;
        if ( $cutoff>0 )
            $this->_cutoff = $cutoff;
    }

    /// set maximum query time, in milliseconds, per-index
    /// integer, 0 means "do not limit"
    function SetMaxQueryTime ( $max )
    {
        assert ( is_int($max) );
        assert ( $max>=0 );
        $this->_maxquerytime = $max;
    }

    /// set matching mode
    function SetMatchMode ( $mode )
    {
        assert ( $mode==SPH_MATCH_ALL
            || $mode==SPH_MATCH_ANY
            || $mode==SPH_MATCH_PHRASE
            || $mode==SPH_MATCH_BOOLEAN
            || $mode==SPH_MATCH_EXTENDED
            || $mode==SPH_MATCH_FULLSCAN
            || $mode==SPH_MATCH_EXTENDED2 );
        $this->_mode = $mode;
    }

    /// set ranking mode
    function SetRankingMode ( $ranker )
    {
        assert ( $ranker==SPH_RANK_PROXIMITY_BM25
            || $ranker==SPH_RANK_BM25
            || $ranker==SPH_RANK_NONE
            || $ranker==SPH_RANK_WORDCOUNT
            || $ranker==SPH_RANK_PROXIMITY );
        $this->_ranker = $ranker;
    }

    /// set matches sorting mode
    function SetSortMode ( $mode, $sortby="" )
    {
        assert (
            $mode==SPH_SORT_RELEVANCE ||
            $mode==SPH_SORT_ATTR_DESC ||
            $mode==SPH_SORT_ATTR_ASC ||
            $mode==SPH_SORT_TIME_SEGMENTS ||
            $mode==SPH_SORT_EXTENDED ||
            $mode==SPH_SORT_EXPR );
        assert ( is_string($sortby) );
        assert ( $mode==SPH_SORT_RELEVANCE || strlen($sortby)>0 );

        $this->_sort = $mode;
        $this->_sortby = $sortby;
    }

    /// bind per-field weights by order
    /// DEPRECATED; use SetFieldWeights() instead
    function SetWeights ( $weights )
    {
        assert ( is_array($weights) );
        foreach ( $weights as $weight )
            assert ( is_int($weight) );

        $this->_weights = $weights;
    }

    /// bind per-field weights by name
    function SetFieldWeights ( $weights )
    {
        assert ( is_array($weights) );
        foreach ( $weights as $name=>$weight )
        {
            assert ( is_string($name) );
            assert ( is_int($weight) );
        }
        $this->_fieldweights = $weights;
    }

    /// bind per-index weights by name
    function SetIndexWeights ( $weights )
    {
        assert ( is_array($weights) );
        foreach ( $weights as $index=>$weight )
        {
            assert ( is_string($index) );
            assert ( is_int($weight) );
        }
        $this->_indexweights = $weights;
    }

    /// set IDs range to match
    /// only match records if document ID is beetwen $min and $max (inclusive)
    function SetIDRange ( $min, $max )
    {
        assert ( is_numeric($min) );
        assert ( is_numeric($max) );
        assert ( $min<=$max );
        $this->_min_id = $min;
        $this->_max_id = $max;
    }

    /// set values set filter
    /// only match records where $attribute value is in given set
    function SetFilter ( $attribute, $values, $exclude=false )
    {
        assert ( is_string($attribute) );
        assert ( is_array($values) );
        assert ( count($values) );

        if ( is_array($values) && count($values) )
        {
            foreach ( $values as $value )
                assert ( is_numeric($value) );

            $this->_filters[] = array ( "type"=>SPH_FILTER_VALUES, "attr"=>$attribute, "exclude"=>$exclude, "values"=>$values );
        }
    }

    /// set range filter
    /// only match records if $attribute value is beetwen $min and $max (inclusive)
    function SetFilterRange ( $attribute, $min, $max, $exclude=false )
    {
        assert ( is_string($attribute) );
        assert ( is_numeric($min) );
        assert ( is_numeric($max) );
        assert ( $min<=$max );

        $this->_filters[] = array ( "type"=>SPH_FILTER_RANGE, "attr"=>$attribute, "exclude"=>$exclude, "min"=>$min, "max"=>$max );
    }

    /// set float range filter
    /// only match records if $attribute value is beetwen $min and $max (inclusive)
    function SetFilterFloatRange ( $attribute, $min, $max, $exclude=false )
    {
        assert ( is_string($attribute) );
        assert ( is_float($min) );
        assert ( is_float($max) );
        assert ( $min<=$max );

        $this->_filters[] = array ( "type"=>SPH_FILTER_FLOATRANGE, "attr"=>$attribute, "exclude"=>$exclude, "min"=>$min, "max"=>$max );
    }

    /// setup anchor point for geosphere distance calculations
    /// required to use @geodist in filters and sorting
    /// latitude and longitude must be in radians
    function SetGeoAnchor ( $attrlat, $attrlong, $lat, $long )
    {
        assert ( is_string($attrlat) );
        assert ( is_string($attrlong) );
        assert ( is_float($lat) );
        assert ( is_float($long) );

        $this->_anchor = array ( "attrlat"=>$attrlat, "attrlong"=>$attrlong, "lat"=>$lat, "long"=>$long );
    }

    /// set grouping attribute and function
    function SetGroupBy ( $attribute, $func, $groupsort="@group desc" )
    {
        assert ( is_string($attribute) );
        assert ( is_string($groupsort) );
        assert ( $func==SPH_GROUPBY_DAY
            || $func==SPH_GROUPBY_WEEK
            || $func==SPH_GROUPBY_MONTH
            || $func==SPH_GROUPBY_YEAR
            || $func==SPH_GROUPBY_ATTR
            || $func==SPH_GROUPBY_ATTRPAIR );

        $this->_groupby = $attribute;
        $this->_groupfunc = $func;
        $this->_groupsort = $groupsort;
    }

    /// set count-distinct attribute for group-by queries
    function SetGroupDistinct ( $attribute )
    {
        assert ( is_string($attribute) );
        $this->_groupdistinct = $attribute;
    }

    /// set distributed retries count and delay
    function SetRetries ( $count, $delay=0 )
    {
        assert ( is_int($count) && $count>=0 );
        assert ( is_int($delay) && $delay>=0 );
        $this->_retrycount = $count;
        $this->_retrydelay = $delay;
    }

    /// set result set format (hash or array; hash by default)
    /// PHP specific; needed for group-by-MVA result sets that may contain duplicate IDs
    function SetArrayResult ( $arrayresult )
    {
        assert ( is_bool($arrayresult) );
        $this->_arrayresult = $arrayresult;
    }

    /// set attribute values override
    /// there can be only one override per attribute
    /// $values must be a hash that maps document IDs to attribute values
    function SetOverride ( $attrname, $attrtype, $values )
    {
        assert ( is_string ( $attrname ) );
        assert ( in_array ( $attrtype, array ( SPH_ATTR_INTEGER, SPH_ATTR_TIMESTAMP, SPH_ATTR_BOOL, SPH_ATTR_FLOAT, SPH_ATTR_BIGINT ) ) );
        assert ( is_array ( $values ) );

        $this->_overrides[$attrname] = array ( "attr"=>$attrname, "type"=>$attrtype, "values"=>$values );
    }

    /// set select-list (attributes or expressions), SQL-like syntax
    function SetSelect ( $select )
    {
        assert ( is_string ( $select ) );
        $this->_select = $select;
    }

    //////////////////////////////////////////////////////////////////////////////

    /// clear all filters (for multi-queries)
    function ResetFilters ()
    {
        $this->_filters = array();
        $this->_anchor = array();
    }

    /// clear groupby settings (for multi-queries)
    function ResetGroupBy ()
    {
        $this->_groupby		= "";
        $this->_groupfunc	= SPH_GROUPBY_DAY;
        $this->_groupsort	= "@group desc";
        $this->_groupdistinct= "";
    }

    /// clear all attribute value overrides (for multi-queries)
    function ResetOverrides ()
    {
        $this->_overrides = array ();
    }

    //////////////////////////////////////////////////////////////////////////////

    /// connect to searchd server, run given search query through given indexes,
    /// and return the search results
    function Query ( $query, $index="*", $comment="" )
    {
        assert ( empty($this->_reqs) );

        $this->AddQuery ( $query, $index, $comment );
        $results = $this->RunQueries ();
        $this->_reqs = array (); // just in case it failed too early

        if ( !is_array($results) )
            return false; // probably network error; error message should be already filled

        $this->_error = $results[0]["error"];
        $this->_warning = $results[0]["warning"];
        if ( $results[0]["status"]==SEARCHD_ERROR )
            return false;
        else
            return $results[0];
    }

    /// helper to pack floats in network byte order
    function _PackFloat ( $f )
    {
        $t1 = pack ( "f", $f ); // machine order
        list(,$t2) = unpack ( "L*", $t1 ); // int in machine order
        return pack ( "N", $t2 );
    }

    /// add query to multi-query batch
    /// returns index into results array from RunQueries() call
    function AddQuery ( $query, $index="*", $comment="" )
    {
        // mbstring workaround
        $this->_MBPush ();

        // build request
        $req = pack ( "NNNNN", $this->_offset, $this->_limit, $this->_mode, $this->_ranker, $this->_sort ); // mode and limits
        $req .= pack ( "N", strlen($this->_sortby) ) . $this->_sortby;
        $req .= pack ( "N", strlen($query) ) . $query; // query itself
        $req .= pack ( "N", count($this->_weights) ); // weights
        foreach ( $this->_weights as $weight )
            $req .= pack ( "N", (int)$weight );
        $req .= pack ( "N", strlen($index) ) . $index; // indexes
        $req .= pack ( "N", 1 ); // id64 range marker
        $req .= sphPackU64 ( $this->_min_id ) . sphPackU64 ( $this->_max_id ); // id64 range

        // filters
        $req .= pack ( "N", count($this->_filters) );
        foreach ( $this->_filters as $filter )
        {
            $req .= pack ( "N", strlen($filter["attr"]) ) . $filter["attr"];
            $req .= pack ( "N", $filter["type"] );
            switch ( $filter["type"] )
            {
                case SPH_FILTER_VALUES:
                    $req .= pack ( "N", count($filter["values"]) );
                    foreach ( $filter["values"] as $value )
                        $req .= sphPackI64 ( $value );
                    break;

                case SPH_FILTER_RANGE:
                    $req .= sphPackI64 ( $filter["min"] ) . sphPackI64 ( $filter["max"] );
                    break;

                case SPH_FILTER_FLOATRANGE:
                    $req .= $this->_PackFloat ( $filter["min"] ) . $this->_PackFloat ( $filter["max"] );
                    break;

                default:
                    assert ( 0 && "internal error: unhandled filter type" );
            }
            $req .= pack ( "N", $filter["exclude"] );
        }

        // group-by clause, max-matches count, group-sort clause, cutoff count
        $req .= pack ( "NN", $this->_groupfunc, strlen($this->_groupby) ) . $this->_groupby;
        $req .= pack ( "N", $this->_maxmatches );
        $req .= pack ( "N", strlen($this->_groupsort) ) . $this->_groupsort;
        $req .= pack ( "NNN", $this->_cutoff, $this->_retrycount, $this->_retrydelay );
        $req .= pack ( "N", strlen($this->_groupdistinct) ) . $this->_groupdistinct;

        // anchor point
        if ( empty($this->_anchor) )
        {
            $req .= pack ( "N", 0 );
        } else
        {
            $a =& $this->_anchor;
            $req .= pack ( "N", 1 );
            $req .= pack ( "N", strlen($a["attrlat"]) ) . $a["attrlat"];
            $req .= pack ( "N", strlen($a["attrlong"]) ) . $a["attrlong"];
            $req .= $this->_PackFloat ( $a["lat"] ) . $this->_PackFloat ( $a["long"] );
        }

        // per-index weights
        $req .= pack ( "N", count($this->_indexweights) );
        foreach ( $this->_indexweights as $idx=>$weight )
            $req .= pack ( "N", strlen($idx) ) . $idx . pack ( "N", $weight );

        // max query time
        $req .= pack ( "N", $this->_maxquerytime );

        // per-field weights
        $req .= pack ( "N", count($this->_fieldweights) );
        foreach ( $this->_fieldweights as $field=>$weight )
            $req .= pack ( "N", strlen($field) ) . $field . pack ( "N", $weight );

        // comment
        $req .= pack ( "N", strlen($comment) ) . $comment;

        // attribute overrides
        $req .= pack ( "N", count($this->_overrides) );
        foreach ( $this->_overrides as $key => $entry )
        {
            $req .= pack ( "N", strlen($entry["attr"]) ) . $entry["attr"];
            $req .= pack ( "NN", $entry["type"], count($entry["values"]) );
            foreach ( $entry["values"] as $id=>$val )
            {
                assert ( is_numeric($id) );
                assert ( is_numeric($val) );

                $req .= sphPackU64 ( $id );
                switch ( $entry["type"] )
                {
                    case SPH_ATTR_FLOAT:	$req .= $this->_PackFloat ( $val ); break;
                    case SPH_ATTR_BIGINT:	$req .= sphPackI64 ( $val ); break;
                    default:				$req .= pack ( "N", $val ); break;
                }
            }
        }

        // select-list
        $req .= pack ( "N", strlen($this->_select) ) . $this->_select;

        // mbstring workaround
        $this->_MBPop ();

        // store request to requests array
        $this->_reqs[] = $req;
        return count($this->_reqs)-1;
    }

    /// connect to searchd, run queries batch, and return an array of result sets
    function RunQueries ()
    {
        if ( empty($this->_reqs) )
        {
            $this->_error = "no queries defined, issue AddQuery() first";
            return false;
        }

        // mbstring workaround
        $this->_MBPush ();

        if (!( $fp = $this->_Connect() ))
        {
            $this->_MBPop ();
            return false;
        }

        // send query, get response
        $nreqs = count($this->_reqs);
        $req = join ( "", $this->_reqs );
        $len = 4+strlen($req);
        $req = pack ( "nnNN", SEARCHD_COMMAND_SEARCH, VER_COMMAND_SEARCH, $len, $nreqs ) . $req; // add header

        if ( !( $this->_Send ( $fp, $req, $len+8 ) ) ||
            !( $response = $this->_GetResponse ( $fp, VER_COMMAND_SEARCH ) ) )
        {
            $this->_MBPop ();
            return false;
        }

        // query sent ok; we can reset reqs now
        $this->_reqs = array ();

        // parse and return response
        return $this->_ParseSearchResponse ( $response, $nreqs );
    }

    /// parse and return search query (or queries) response
    function _ParseSearchResponse ( $response, $nreqs )
    {
        $p = 0; // current position
        $max = strlen($response); // max position for checks, to protect against broken responses

        $results = array ();
        for ( $ires=0; $ires<$nreqs && $p<$max; $ires++ )
        {
            $results[] = array();
            $result =& $results[$ires];

            $result["error"] = "";
            $result["warning"] = "";

            // extract status
            list(,$status) = unpack ( "N*", substr ( $response, $p, 4 ) ); $p += 4;
            $result["status"] = $status;
            if ( $status!=SEARCHD_OK )
            {
                list(,$len) = unpack ( "N*", substr ( $response, $p, 4 ) ); $p += 4;
                $message = substr ( $response, $p, $len ); $p += $len;

                if ( $status==SEARCHD_WARNING )
                {
                    $result["warning"] = $message;
                } else
                {
                    $result["error"] = $message;
                    continue;
                }
            }

            // read schema
            $fields = array ();
            $attrs = array ();

            list(,$nfields) = unpack ( "N*", substr ( $response, $p, 4 ) ); $p += 4;
            while ( $nfields-->0 && $p<$max )
            {
                list(,$len) = unpack ( "N*", substr ( $response, $p, 4 ) ); $p += 4;
                $fields[] = substr ( $response, $p, $len ); $p += $len;
            }
            $result["fields"] = $fields;

            list(,$nattrs) = unpack ( "N*", substr ( $response, $p, 4 ) ); $p += 4;
            while ( $nattrs-->0 && $p<$max  )
            {
                list(,$len) = unpack ( "N*", substr ( $response, $p, 4 ) ); $p += 4;
                $attr = substr ( $response, $p, $len ); $p += $len;
                list(,$type) = unpack ( "N*", substr ( $response, $p, 4 ) ); $p += 4;
                $attrs[$attr] = $type;
            }
            $result["attrs"] = $attrs;

            // read match count
            list(,$count) = unpack ( "N*", substr ( $response, $p, 4 ) ); $p += 4;
            list(,$id64) = unpack ( "N*", substr ( $response, $p, 4 ) ); $p += 4;

            // read matches
            $idx = -1;
            while ( $count-->0 && $p<$max )
            {
                // index into result array
                $idx++;

                // parse document id and weight
                if ( $id64 )
                {
                    $doc = sphUnpackU64 ( substr ( $response, $p, 8 ) ); $p += 8;
                    list(,$weight) = unpack ( "N*", substr ( $response, $p, 4 ) ); $p += 4;
                }
                else
                {
                    list ( $doc, $weight ) = array_values ( unpack ( "N*N*",
                        substr ( $response, $p, 8 ) ) );
                    $p += 8;
                    $doc = sphFixUint($doc);
                }
                $weight = sprintf ( "%u", $weight );

                // create match entry
                if ( $this->_arrayresult )
                    $result["matches"][$idx] = array ( "id"=>$doc, "weight"=>$weight );
                else
                    $result["matches"][$doc]["weight"] = $weight;

                // parse and create attributes
                $attrvals = array ();
                foreach ( $attrs as $attr=>$type )
                {
                    // handle 64bit ints
                    if ( $type==SPH_ATTR_BIGINT )
                    {
                        $attrvals[$attr] = sphUnpackI64 ( substr ( $response, $p, 8 ) ); $p += 8;
                        continue;
                    }

                    // handle floats
                    if ( $type==SPH_ATTR_FLOAT )
                    {
                        list(,$uval) = unpack ( "N*", substr ( $response, $p, 4 ) ); $p += 4;
                        list(,$fval) = unpack ( "f*", pack ( "L", $uval ) );
                        $attrvals[$attr] = $fval;
                        continue;
                    }

                    // handle everything else as unsigned ints
                    list(,$val) = unpack ( "N*", substr ( $response, $p, 4 ) ); $p += 4;
                    if ( $type & SPH_ATTR_MULTI )
                    {
                        $attrvals[$attr] = array ();
                        $nvalues = $val;
                        while ( $nvalues-->0 && $p<$max )
                        {
                            list(,$val) = unpack ( "N*", substr ( $response, $p, 4 ) ); $p += 4;
                            $attrvals[$attr][] = sphFixUint($val);
                        }
                    } else
                    {
                        $attrvals[$attr] = sphFixUint($val);
                    }
                }

                if ( $this->_arrayresult )
                    $result["matches"][$idx]["attrs"] = $attrvals;
                else
                    $result["matches"][$doc]["attrs"] = $attrvals;
            }

            list ( $total, $total_found, $msecs, $words ) =
                array_values ( unpack ( "N*N*N*N*", substr ( $response, $p, 16 ) ) );
            $result["total"] = sprintf ( "%u", $total );
            $result["total_found"] = sprintf ( "%u", $total_found );
            $result["time"] = sprintf ( "%.3f", $msecs/1000 );
            $p += 16;

            while ( $words-->0 && $p<$max )
            {
                list(,$len) = unpack ( "N*", substr ( $response, $p, 4 ) ); $p += 4;
                $word = substr ( $response, $p, $len ); $p += $len;
                list ( $docs, $hits ) = array_values ( unpack ( "N*N*", substr ( $response, $p, 8 ) ) ); $p += 8;
                $result["words"][$word] = array (
                    "docs"=>sprintf ( "%u", $docs ),
                    "hits"=>sprintf ( "%u", $hits ) );
            }
        }

        $this->_MBPop ();
        return $results;
    }

    /////////////////////////////////////////////////////////////////////////////
    // excerpts generation
    /////////////////////////////////////////////////////////////////////////////

    /// connect to searchd server, and generate exceprts (snippets)
    /// of given documents for given query. returns false on failure,
    /// an array of snippets on success
    function BuildExcerpts ( $docs, $index, $words, $opts=array() )
    {
        assert ( is_array($docs) );
        assert ( is_string($index) );
        assert ( is_string($words) );
        assert ( is_array($opts) );

        $this->_MBPush ();

        if (!( $fp = $this->_Connect() ))
        {
            $this->_MBPop();
            return false;
        }

        /////////////////
        // fixup options
        /////////////////

        if ( !isset($opts["before_match"]) )		$opts["before_match"] = "<b>";
        if ( !isset($opts["after_match"]) )			$opts["after_match"] = "</b>";
        if ( !isset($opts["chunk_separator"]) )		$opts["chunk_separator"] = " ... ";
        if ( !isset($opts["limit"]) )				$opts["limit"] = 256;
        if ( !isset($opts["around"]) )				$opts["around"] = 5;
        if ( !isset($opts["exact_phrase"]) )		$opts["exact_phrase"] = false;
        if ( !isset($opts["single_passage"]) )		$opts["single_passage"] = false;
        if ( !isset($opts["use_boundaries"]) )		$opts["use_boundaries"] = false;
        if ( !isset($opts["weight_order"]) )		$opts["weight_order"] = false;

        /////////////////
        // build request
        /////////////////

        // v.1.0 req
        $flags = 1; // remove spaces
        if ( $opts["exact_phrase"] )	$flags |= 2;
        if ( $opts["single_passage"] )	$flags |= 4;
        if ( $opts["use_boundaries"] )	$flags |= 8;
        if ( $opts["weight_order"] )	$flags |= 16;
        $req = pack ( "NN", 0, $flags ); // mode=0, flags=$flags
        $req .= pack ( "N", strlen($index) ) . $index; // req index
        $req .= pack ( "N", strlen($words) ) . $words; // req words

        // options
        $req .= pack ( "N", strlen($opts["before_match"]) ) . $opts["before_match"];
        $req .= pack ( "N", strlen($opts["after_match"]) ) . $opts["after_match"];
        $req .= pack ( "N", strlen($opts["chunk_separator"]) ) . $opts["chunk_separator"];
        $req .= pack ( "N", (int)$opts["limit"] );
        $req .= pack ( "N", (int)$opts["around"] );

        // documents
        $req .= pack ( "N", count($docs) );
        foreach ( $docs as $doc )
        {
            assert ( is_string($doc) );
            $req .= pack ( "N", strlen($doc) ) . $doc;
        }

        ////////////////////////////
        // send query, get response
        ////////////////////////////

        $len = strlen($req);
        $req = pack ( "nnN", SEARCHD_COMMAND_EXCERPT, VER_COMMAND_EXCERPT, $len ) . $req; // add header
        if ( !( $this->_Send ( $fp, $req, $len+8 ) ) ||
            !( $response = $this->_GetResponse ( $fp, VER_COMMAND_EXCERPT ) ) )
        {
            $this->_MBPop ();
            return false;
        }

        //////////////////
        // parse response
        //////////////////

        $pos = 0;
        $res = array ();
        $rlen = strlen($response);
        for ( $i=0; $i<count($docs); $i++ )
        {
            list(,$len) = unpack ( "N*", substr ( $response, $pos, 4 ) );
            $pos += 4;

            if ( $pos+$len > $rlen )
            {
                $this->_error = "incomplete reply";
                $this->_MBPop ();
                return false;
            }
            $res[] = $len ? substr ( $response, $pos, $len ) : "";
            $pos += $len;
        }

        $this->_MBPop ();
        return $res;
    }


    /////////////////////////////////////////////////////////////////////////////
    // keyword generation
    /////////////////////////////////////////////////////////////////////////////

    /// connect to searchd server, and generate keyword list for a given query
    /// returns false on failure,
    /// an array of words on success
    function BuildKeywords ( $query, $index, $hits )
    {
        assert ( is_string($query) );
        assert ( is_string($index) );
        assert ( is_bool($hits) );

        $this->_MBPush ();

        if (!( $fp = $this->_Connect() ))
        {
            $this->_MBPop();
            return false;
        }

        /////////////////
        // build request
        /////////////////

        // v.1.0 req
        $req  = pack ( "N", strlen($query) ) . $query; // req query
        $req .= pack ( "N", strlen($index) ) . $index; // req index
        $req .= pack ( "N", (int)$hits );

        ////////////////////////////
        // send query, get response
        ////////////////////////////

        $len = strlen($req);
        $req = pack ( "nnN", SEARCHD_COMMAND_KEYWORDS, VER_COMMAND_KEYWORDS, $len ) . $req; // add header
        if ( !( $this->_Send ( $fp, $req, $len+8 ) ) ||
            !( $response = $this->_GetResponse ( $fp, VER_COMMAND_KEYWORDS ) ) )
        {
            $this->_MBPop ();
            return false;
        }

        //////////////////
        // parse response
        //////////////////

        $pos = 0;
        $res = array ();
        $rlen = strlen($response);
        list(,$nwords) = unpack ( "N*", substr ( $response, $pos, 4 ) );
        $pos += 4;
        for ( $i=0; $i<$nwords; $i++ )
        {
            list(,$len) = unpack ( "N*", substr ( $response, $pos, 4 ) );	$pos += 4;
            $tokenized = $len ? substr ( $response, $pos, $len ) : "";
            $pos += $len;

            list(,$len) = unpack ( "N*", substr ( $response, $pos, 4 ) );	$pos += 4;
            $normalized = $len ? substr ( $response, $pos, $len ) : "";
            $pos += $len;

            $res[] = array ( "tokenized"=>$tokenized, "normalized"=>$normalized );

            if ( $hits )
            {
                list($ndocs,$nhits) = array_values ( unpack ( "N*N*", substr ( $response, $pos, 8 ) ) );
                $pos += 8;
                $res [$i]["docs"] = $ndocs;
                $res [$i]["hits"] = $nhits;
            }

            if ( $pos > $rlen )
            {
                $this->_error = "incomplete reply";
                $this->_MBPop ();
                return false;
            }
        }

        $this->_MBPop ();
        return $res;
    }

    function EscapeString ( $string )
    {
        $from = array ( '\\', '(',')','|','-','!','@','~','"','&', '/', '^', '$', '=' );
        $to   = array ( '\\\\', '\(','\)','\|','\-','\!','\@','\~','\"', '\&', '\/', '\^', '\$', '\=' );

        return str_replace ( $from, $to, $string );
    }

    /////////////////////////////////////////////////////////////////////////////
    // attribute updates
    /////////////////////////////////////////////////////////////////////////////

    /// batch update given attributes in given rows in given indexes
    /// returns amount of updated documents (0 or more) on success, or -1 on failure
    function UpdateAttributes ( $index, $attrs, $values, $mva=false )
    {
        // verify everything
        assert ( is_string($index) );
        assert ( is_bool($mva) );

        assert ( is_array($attrs) );
        foreach ( $attrs as $attr )
            assert ( is_string($attr) );

        assert ( is_array($values) );
        foreach ( $values as $id=>$entry )
        {
            assert ( is_numeric($id) );
            assert ( is_array($entry) );
            assert ( count($entry)==count($attrs) );
            foreach ( $entry as $v )
            {
                if ( $mva )
                {
                    assert ( is_array($v) );
                    foreach ( $v as $vv )
                        assert ( is_int($vv) );
                } else
                    assert ( is_int($v) );
            }
        }

        // build request
        $req = pack ( "N", strlen($index) ) . $index;

        $req .= pack ( "N", count($attrs) );
        foreach ( $attrs as $attr )
        {
            $req .= pack ( "N", strlen($attr) ) . $attr;
            $req .= pack ( "N", $mva ? 1 : 0 );
        }

        $req .= pack ( "N", count($values) );
        foreach ( $values as $id=>$entry )
        {
            $req .= sphPackU64 ( $id );
            foreach ( $entry as $v )
            {
                $req .= pack ( "N", $mva ? count($v) : $v );
                if ( $mva )
                    foreach ( $v as $vv )
                        $req .= pack ( "N", $vv );
            }
        }

        // connect, send query, get response
        if (!( $fp = $this->_Connect() ))
            return -1;

        $len = strlen($req);
        $req = pack ( "nnN", SEARCHD_COMMAND_UPDATE, VER_COMMAND_UPDATE, $len ) . $req; // add header
        if ( !$this->_Send ( $fp, $req, $len+8 ) )
            return -1;

        if (!( $response = $this->_GetResponse ( $fp, VER_COMMAND_UPDATE ) ))
            return -1;

        // parse response
        list(,$updated) = unpack ( "N*", substr ( $response, 0, 4 ) );
        return $updated;
    }

    /////////////////////////////////////////////////////////////////////////////
    // persistent connections
    /////////////////////////////////////////////////////////////////////////////

    function Open()
    {
        if ( $this->_socket !== false )
        {
            $this->_error = 'already connected';
            return false;
        }
        if ( !$fp = $this->_Connect() )
            return false;

        // command, command version = 0, body length = 4, body = 1
        $req = pack ( "nnNN", SEARCHD_COMMAND_PERSIST, 0, 4, 1 );
        if ( !$this->_Send ( $fp, $req, 12 ) )
            return false;

        $this->_socket = $fp;
        return true;
    }

    function Close()
    {
        if ( $this->_socket === false )
        {
            $this->_error = 'not connected';
            return false;
        }

        fclose ( $this->_socket );
        $this->_socket = false;

        return true;
    }

    //////////////////////////////////////////////////////////////////////////
    // status
    //////////////////////////////////////////////////////////////////////////

    function Status ()
    {
        $this->_MBPush ();
        if (!( $fp = $this->_Connect() ))
        {
            $this->_MBPop();
            return false;
        }

        $req = pack ( "nnNN", SEARCHD_COMMAND_STATUS, VER_COMMAND_STATUS, 4, 1 ); // len=4, body=1
        if ( !( $this->_Send ( $fp, $req, 12 ) ) ||
            !( $response = $this->_GetResponse ( $fp, VER_COMMAND_STATUS ) ) )
        {
            $this->_MBPop ();
            return false;
        }

        $res = substr ( $response, 4 ); // just ignore length, error handling, etc
        $p = 0;
        list ( $rows, $cols ) = array_values ( unpack ( "N*N*", substr ( $response, $p, 8 ) ) ); $p += 8;

        $res = array();
        for ( $i=0; $i<$rows; $i++ )
            for ( $j=0; $j<$cols; $j++ )
            {
                list(,$len) = unpack ( "N*", substr ( $response, $p, 4 ) ); $p += 4;
                $res[$i][] = substr ( $response, $p, $len ); $p += $len;
            }

        $this->_MBPop ();
        return $res;
    }
}

//
// $Id: sphinxapi.php 2055 2009-11-06 23:09:58Z shodan $
//
